Ctguc acetal



Patented Feb. 3, 1942 cYcLIc mam.

- Clarence Moyle, Midland,ijMich'.,a assignorrto .The Dow ChemicalCompany, Midland, Mich.',.

a corporation of Michigan 3 No Drawing. Application as is, 1941,

' Serial No. 393,226 0 I u 0 4 Claims. (Cl.'260--338) The presentinvention relates to cyclic acetals and is particularly directed to anew; group of chemical compounds having a following formula:

wherein R represents a member of the classcon- I of ethylene glycol.

sisting of methylene, ethylene, alkyl-methylene,

hydroxyalkyl-methylene, and hydroxy-ethylene, and r the cyclic-acetalrin contains not more than 6 members.

I have prepared representative members of this group of compounds andfound them to be yellow or orange crystalline materials difiicultlysoluble in water. These compounds are relatively stable on exposuretoheat, light and. alkali .but

are rather unstable in the presence of aqueous.

. from milliliters ofboiling benzene to obtain acid. They may beemployedas intermediates in the preparation of more complex organicderivatives or as constituents of parasiticidal compositions.

The compounds may be prepared by reacting 3.5-dinitro-salicylaldehydewith a poly-alcohol of tion mixture, appreciable heat of reaction 9 isevolved. The reaction mixture is then heated The following examplesillustrate the invention but are not'to be construedas limiting thesame.

(3'.5'.-dinitro 2' hydrory-phenyZ)-1.3-di0:cola ne I r 4.0 grams (0.019mol) 3.5-dinitro-salicylalde hyde wassuspended in 20.7 grams (0.334 mol)0.5 gram (0.0033 mol) of boron trifluoride as a 45' per cent by weightsolution in ethyl ether, and 12 milliliters of concentrated hydrochloricacid was then added to Q the mixture whereupon appreciable heat ofreaction was evolved. The mixture was heatedand stirred on a .steam bathfor 15, minutes'at a temperature of 80-85 C. and thereafter cooled toroom temperature. .The solid reaction product was recovered byfiltration and recrystallized 4.1 grams of 2-(3.5-dinitro-2hydroxy-phenyl)-1.3-dioxolane as a white crystalline compound melting at134-135? C. and containing 10.99 per cent nitrogen as compared to atheoretical nitrogen content of 10.94 per cent. This compound hastheformula:

i EXAMPLE 2.-2-(3'-.5'-dinitro 2' hydroxy-phenyl) -1.3-dioxane in ethersolution as described in Example 1,242

' grams (0.32 mol) of trimethylene glycol (boiling at 211212 C.), 12milliliters of concentrated and stirred on a steam bath at a temperaturebetween about and C. A heatin period of from 15 minutes to 2 hours isgenerally sufficient for the completion of the reaction. The

mixture is then cooled to room temperature and, I

. the desired product separated therefrom. Where the crude product is inthe form of an oil, the reaction mixture may be diluted with waterand/or cooled, and the product recovered by de-, cantation. The oil isthen warmed to drive oflf traces of unreacted alcohol and cooled inorder to cause crystallization. Where the crude prod not of the reactionis in the form of a solid precipitate, the mixture can be filtered andthe residue either washed with or recrystallized from a suitablesolventand thereafter dried.

hydrochloric acid, and 4.0 grams (0.019 mol) of3.5-dinitroesalicylaldehyde were mixed together and heated on a Steambath for a period of approximately 15 minutes. The crude reactionmixture was thereafter cooled to room temperature, filtered, and the.residue from the filtration recrystallized from 25 milliliters of hotbenzene to obtain 2.0 grams of 2-(3.5'-dinitro-2'- hydroxy-phenyl)-1.3dioxane as a white crystalline compound melting at 11 3-118 C. and

containing 10.79 per cent nitrogen as compared to a theoretical nitrogencontent of 10.4 per cent.

- This compound has the formula:

O-CHi /CH2 O-CH:

0.5 gram (0.0033 mol) of the boron trifluoride EXAMPLE 3.-Mi:ctu-re of2-(3'.5-dinitro-2-hydroxyphenyl) -4-hydro:1:ymethyl-1.3 dioxolane and 2(3'.5 dinitr0-2'-hydr0.ry phenyl) -5- hydrozry-I .3 -cZi0:rane

37.8 grams (0.41 mol) of glycerol. 4.0 grams (0.019 mol) of3.5-dinitro-salicylaldehyde; 0.5 gram (0.0033 mol) of boron trifiuoridein ether solution, and 12 milliliters of concentrated hydro- The otherconstituent of the crude reaction mixture was believed to be2(3.5'-dinitro-2'-hydroxy-phenyl)-5-hydroxy-13-dioxane having theformula:

| ocH, H

In a similar manner 3.5-dinitro-salicylaldehyde may be reacted with suchpoly-alcohols as butylene glycol, amylene glycol, and octylene glycol toobtain compounds fallin within the scope 6 of the present invention.

I claim: 1. A 2-(3'.5'-dinitro-2'-hydroxy-phenyl) cyclic acetal havingthe formula:

wherein R represents a member of the class con- 0 sisting of methylene,ethylene, alkyl-methylene,

hydroxyalkyl-methylene, and hydroxy-ethylene, and the cyclic acetal ringcontains not more than 6 carbon atoms.

2. A 2-(3'.5'-dinitro-2'-hydroxy-phenyl) cyclic 5 acetal having theformula:

wherein n is an integer not greater than 2.

3. 2-(3.5'-dinitro-2'-hydroxy-phenyl) -1.3-dioxolane.

4. 2-(3'.5-dinitro-2'-hydroxy-phenyl) -l.3-dioxane.

CLARENCE L. MOYLE.

